U.S. patent number 5,689,903 [Application Number 08/544,517] was granted by the patent office on 1997-11-25 for protective waterproof shoe.
Invention is credited to Johann Aumann.
United States Patent |
5,689,903 |
Aumann |
November 25, 1997 |
Protective waterproof shoe
Abstract
Footwear includes a shaft and a laminate which lines the shaft.
The laminate has a waterproof, water vapor permeable functional
layer, a rigid protective cap is between the shaft and the
laminate. In the toe area, the laminate is designed as a bootie. An
insole which serves as a mechanical protection between the laminate
and the protective cap is located between the outsole side of the
bootie and an outsole side edge of the protective cap.
Inventors: |
Aumann; Johann (D-83052
Bruckmuhl, DE) |
Family
ID: |
6534787 |
Appl.
No.: |
08/544,517 |
Filed: |
October 18, 1995 |
Foreign Application Priority Data
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Dec 2, 1994 [DE] |
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44 43 002.7 |
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Current U.S.
Class: |
36/77R; 36/12;
36/55 |
Current CPC
Class: |
A43B
7/32 (20130101); A43B 7/125 (20130101) |
Current International
Class: |
A43B
7/00 (20060101); A43B 7/12 (20060101); A43B
7/32 (20060101); A43C 013/14 (); A43B 013/28 ();
A43B 023/26 () |
Field of
Search: |
;36/10,12,55,43,44,83,77R |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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0080710 |
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Jun 1983 |
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EP |
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0298360 |
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Jan 1989 |
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EP |
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4000156 |
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Jul 1991 |
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DE |
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9200099.1 |
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Apr 1992 |
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DE |
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9404207.1 |
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May 1994 |
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DE |
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4311768 |
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Oct 1994 |
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DE |
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Primary Examiner: Dayoan; B.
Attorney, Agent or Firm: Samuels; Gary A.
Claims
I claim:
1. Footwear with:
(a) a shaft;
(b) a laminate lining the shaft, having a waterproof and water
vapor permeable functional layer;
(c) an insole connected to the laminate;
(d) a waterproof plastic outsole injection molded to the lower part
of the shaft;
(e) wherein the shaft material itself ends at a certain distance
from the outsole side end of the laminate in the middle foot area
and heel area; and
(f) wherein the outsole side end of the shaft material itself is
connected to the insole and the outsole-side end of the laminate in
a middle foot area and heel area of the footwear through a
connection material formed by a porous connection material which
can be penetrated by the outsole material when the latter is in the
liquid state during the injection molding process;
characterized by
(g) a rigid protective cap which is arranged in a toe area of the
footwear between the shaft and the laminate and whose underside
facing the outsole goes under the insole over a predetermined
width;
(h) a bootie consisting of a laminate which is arranged in the toe
area on the side of the insole facing the foot where it lines the
inside of the footwear; and
(I) wherein the shaft material is connected to the insole
circumference in the toe area on the side of the insole facing the
outsole by a glued connection.
2. Footwear of claim 1, characterized in that the bootie comprises
two laminate pieces which project into the toe area from the
laminate which lines the shaft and which are connected with each
other by a seam which is sealed against the ingress of water by an
adhesively bonded seam sealing tape.
3. Footwear of claim 1, characterized in that the bootie has a
laminate piece which corresponds to the contours of the toe area of
the footwear and which is connected to the laminate which lines the
toe area of the shaft by a seam which is sealed against the ingress
of water by an adhesively bonded seam sealing tape.
4. Footwear of one of claims 1, 2 or 3, characterized in that the
porous connection material is formed by a net band, preferably
consisting of monofilic fibers.
Description
FIELD OF THE INVENTION
The invention relates to footwear. More specifically, it relates to
waterproof, water vapor permeable footwear.
BACKGROUND OF THE INVENTION
In the course of the last years, waterproof, yet water vapor
permeable membrane material has been increasingly used to produce
waterproof clothing. Being permeable to vapor, such materials are
very comfortable to wear. An example for such a membrane material
is expanded polytetrafluoroethylene (PTFE) consisting of polyester
or a microporous polyurethane coating.
Recently such membrane materials have also been used to make
waterproof footwear. In this application the inside of at least the
shoe shaft is clad with such a membrane material, which is referred
to as "functional layer" herein. An example is shown in European
printed publication EP-A2-0080710. The cladding is mostly formed by
a lining in the form of a laminate which comprises the functional
layer and a textile layer on its side facing the inside of the
shoe.
In such constructions the seams, which are produced when the shoe
shaft is sewn to the lining and the insole, become a problem
because at the stitched parts the functional layer becomes
perforated and permeable to water.
To overcome this problem, an injection-molding process can be used
In which the underside of the footwear or the insole and the
underside of the shaft with the functional layer, which may be sewn
to the insole, is surrounded by a caoutchuc or plastic sole forming
the outsole. The connection seam between the shaft and the lining
and the insole is enclosed by the caoutchuc or rubber outsole. The
shaft usually consists of leather or a textile fabric, e.g. made
from synthetic fibers.
The injection-molded plastic sole seals the seam between the
functional layer and the shaft and insole against direct contact
with water, but the mentioned shaft materials, in particular
leather shafts, typically conduct water in their longitudinal
direction. This process involves capillary effects. If the shaft
area which is not covered by the plastic sole becomes wet, this
longitudinal conduction effect will make water creep along the
shaft up to the seam located on the inside of the injection-molded
plastic sole where it can penetrate the functional layer through
the holes produced by sewing.
The functional layer is usually located on the inside of a laminate
which is coated with a protective textile on the side facing the
shaft and with a lining material on the side facing inwards. Since
shoes are normally produced in mass production, the formation of
water bridges on the lower ends of shaft and lining can hardly be
prevented, at least not in a cost-efficient way. These water
bridges may be formed by threads which project from the cut lining
piece and reach over the cut end of the functional layer to the
shaft material. It is in particular when the shaft material
consists of a textile fabric that the shaft end and the lining end
may not be cut on the same level so that threads or parts of the
textile shaft material bridge the cut end of the functional layer
and form a moisture bridge reaching up to the lining of the
shoe.
The lining material which clads the inside of the shoe is usually
absorbent and water conducting. Water entering the shoe along the
shaft and penetrating through the seam and/or the water bridges
mentioned above will creep along the lining into the shoe.
To overcome this problem, printed publication EP-B1-0298360
describes the use of waterproof footwear comprising a shaft, a
shaft lining with a waterproof and water vapor permeable
microporous functional layer, an insole the circumference of which
is sewn to the lower end area of the lining and an outsole
consisting of a waterproof plastic material injection-molded to the
lower shaft area. The lower shaft area located in the outsole area
is sewn to a porous material which can be penetrated by the plastic
outsole material, which is liquid during the injection-molding
process. In this state of the art footwear the shaft material is
cut such in the sole area that it ends at some distance from the
lower lining end. The end of the shaft material itself is connected
to the insole and the lower lining end through a connection
material formed by the porous material; the porous connection
material is sewn to the shaft material itself on one end, but not
to the lining and to the insole by a seam on the other end. This
state of the art footwear can be produced by a state of the art
process, which is also known from printed publication
EP-B1-0298360. The lining is provided with a waterproof and water
vapor permeable microporous functional lining, then the lower end
of the shaft material itself is cut such that it has a certain
height distance from the lower end of the lining and is extended
using the porous material as a connection material. Then the lining
and the end of the porous connection material facing away from the
shaft material itself are sewn together and sewn to the
circumference of an insole at their lower ends through a seam.
Finally the plastic outsole is mounted by injection molding.
As shown in FIG. 1 a shoe of the type described in EP-B1-0298360
has a shaft S which consists, e.g., of leather or a textile fabric,
preferably plastic. The inside of the shaft S is lined with a
laminate L which serves as an inner lining and comprises a
waterproof, water-vapor permeable functional layer or membrane M
which is lined with a textile fabric T on the side facing the shaft
S and with a lining material F on the side facing the inside of the
shoe. The lining material and the textile fabric T form a
mechanical protection for the functional layer M. The composite
assembly comprising the shaft S and the laminate L is sewn to the
edge of an insole B on its lower end, the corresponding seam is
designated as N. A sole K consisting of a suitable waterproof
plastic material is injection molded to the underside of the insole
B and the lower area of the shaft S sewn thereto. The upper edge O
of the sole K lies so high that the seam N is enclosed by the sole
K. The seam N is thus sealed against direct contact with water.
However, water which comes into contact with the part of the shaft
S which lies outside of the sole K may creep along the shaft on the
inside of the sole K up to the seam where it can go through seam
stitch holes in the functional layer M and reach the interior of
the shoe.
In state of the art footwear as shown in FIG. 2, the shaft S does
not reach up to the insole B, but the lower shaft end has a
distance to the insole edge. This distance is bridged by a
perforated or porous connection material V. The outer edge of the
connection material V is sewn to the inner edge of the shaft S by a
first seam N1. The laminate L, however, is not sewn to the shaft S
at this spot. The other end of the connection material V is sewn to
the insole B together with the inner end of the laminate L by a
second seam N2.
The porous connection material V is preferably realized by a net
band consisting of monofilic synthetic fibers. It is particularly
favorable to select a mesh width of min. 1.5 mm. Suitable synthetic
fibers are polyamide or polyester.
When the sole K is injection molded to the shoe, liquid sole
material penetrates the pores or holes or loops of the connection
material V until it reaches the outside of the laminate L so that
the seam stitch holes of the second seam N2 are sealed with the
sole plastic.
Since the lower shaft area is formed by a connection material V
with holes or pores which is connected to the shaft itself, water
conducted by the shaft itself cannot reach the seam connecting
shaft, lining and insole so that even water bridges formed by the
seam and by threads or fabric pieces forming bridges across the
functional layer cannot have any effect because the water conducted
by the shaft cannot reach them.
Even if footwear of this type and the process described for its
production has proven very useful for various types of casual
shoes, new problems arise when footwear needs to be reinforced by
incorporating a rigid protective cap, e.g. of steel or
thermoplastic material.
In a protective shoe with a protective cap this state of the art
principle cannot be applied in the toe area because the shell
material is under high tension after insertion of the protective
cap and a Strobel sewing machine, which is used for sewing, cannot
grasp the material such that the connection material can be sewn to
the lining or insole.
Instead, in protective shoes the lining is usually stroble-sewn to
the insole at the front shoe shaft part, then the protective cap is
inserted between the lining and the face material and then the face
material is manually glued to the insole.
SUMMARY OF THE INVENTION
The object of the invention is to provide for footwear with a
protective cap which is arranged in the toe area between the
footwear shaft and a laminate lining the shaft whose underside
facing the outsole goes under the insole over a predetermined
width. A bootie consisting of a laminate is arranged in the toe
area on the side of the insole facing the foot. A shaft material is
connected to the insole circumference in the toe area on the side
of the insole facing the outsole by a glued connection.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following, the invention will be explained in more detail
with reference to an embodiment and FIGS. 1-4.
FIG. 1 is a cross-sectional drawing of the middle foot area of
state of the art footwear.
FIG. 2 is a cross-sectional drawing of the middle foot area of
state of the art footwear.
FIG. 3 is a top view of the underside of the insole of footwear
designed according to the invention.
FIG. 4 is a cross-sectional drawing of the toe area of footwear
designed according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 3 is a view from below of the underside of footwear to which
the outsole is not yet mounted and which has the same design in the
middle foot and heel area as the footwear shown in FIG. 2.
In the footwear shown in FIG. 3 the insole has two separate insole
pieces, namely a rear insole part B1 in the area of the middle foot
or the heel and a front insole area B2 in the toe area. In the toe
area the insole part B2 is visible within the shaft material S
which reaches down to the shoe underside. In the toe area the
footwear has a rigid protective cap SK consisting of a highly
pressure and impact resistant material, in the area between the
shaft S and the laminate L. The area facing the outsole goes under
the insole part B2 on its outside. The laminate L facing the
interior of the shoe consists of two laminate flap pieces which are
put together by a seam SN on the inside of the insole piece B2 to
form a partial sock (bootie) in the toe area. In the toe area the
shaft material S is guided over the protective cap SK and connected
to the outside of the insole part B2 by a glued lasting connection
KN.
The front insole piece B2 is located between the laminate L and the
area of the protective cap SK to protect the laminate L against
mechanical damage by the protective cap SK which goes over the
insole piece B2. The insole piece B2 is glued onto the laminate
outside. The part of the bootie facing the middle foot area is
connected to the insole piece B1 by a seam N2, which may be a sewn
seam.
The two insole pieces B1 and B2 may consist of different materials.
The insole piece B1 may consist of a fleece material. The insole
material B2 may consist of a harder material, such as leather,
cardboard or wood.
The entire insole may also consist of a single piece, in this case
a sturdy material as is suitable for a toe area. In this case the
seam N2' is designed as a glued seam.
FIG. 4 shows a cross-sectional view of the toe area of the footwear
shown in FIG. 3. From the drawing it is seen that the protective
cap SK is located between the shaft S and the partial sock
consisting of the laminate. The bootie may consist of two laminate
pieces connected by a sock seam SN.
It is advantageous to seal this sock seam SN by applying an
adhesively bonded waterproof seam sealing tape KSB to the underside
of the bootie against the ingress of water.
The bootie may also be made from a piece which is adapted to the
contours of the toe area of the shoe and which is connected to the
laminate lining in the toe area of the shaft by means of a seam. In
this case, too, the seam is sealed against the ingress of water by
an adhesive seam tape.
Depending on whether the footwear of the invention is constructed
with a one-piece insole or with two separate insole pieces, various
manufacturing processes can be used.
In both cases at first a tape-shaped connection material V,
preferably in the form of a net consisting of monofilic fibers, is
connected to the edge of the cut-to-size lag facing the outsole in
the area of the middle foot and heel. Then a laminate piece is cut
to size such that its shape matches the shaft piece. Its toe area
is then closed in the form of a bootie on the outsole side by means
of a laminate piece. This laminate piece may be formed either by
two laminate pieces connected to the cut-to-size laminate piece
which are connected with each other by a waterproof seam to form a
laminate bootie, as shown in the embodiment of FIG. 3, or the
laminate piece may be formed by a laminate piece which corresponds
to the toe contours of the shoe and which is connected to the
cut-to-size laminate piece by a waterproof seam.
After such a laminate bootie has been produced, the next processing
step depends on whether a one-piece or two-piece insole is
used.
If a two-piece insole is used, the free edge of the connection
material and the edge of the outsole facing the middle foot area
are connected to the first insole part B1 then the second insole
piece B2 is connected to the outsole side of the bootie.
If a one-piece insole is used, the toe area of the insole is
connected to the outsole-side of the bootie on the one hand and the
free edge of the connecting material and the edge of the outsole
side of the bootie which faces the middle foot area on the other
hand are connected to the insole.
In both cases, i.e., no matter whether a one-piece or two-piece
insole is used, the protective cap SK is mounted between the shaft
S and the laminate L in the toe area in such a way that the
underside of the protective cap facing the outsole K goes under the
circumferential edge of the insole on its outsole side.
Subsequently the outsole side end of the shaft S is connected to
the outsole side of the second insole piece B2 or of the one-piece
insole in the toe area. Finally the outsole is connected by
injection molding.
Materials suitable for the waterproof, water vapor permeable
functional layer of the laminate comprise microporous expanded
polytetrafluoroethylene (PTFE) as described in U.S. Pat. Nos.
3,953,566 and 4,187,390; expanded PTFE provided with hydrophilic
impregnating agents and/or layers as described in U.S. Pat. No.
4,194,041; breathable polyurethane layers or elastomers, such as
copolyetherester and laminates thereof, as described in U.S. Pat.
Nos. 4,725,481 and 4,493,870.
* * * * *